Leadership, to Americans, is a familiar concept. Go into any bookstore, and the number of tomes with the word in the title--Total Leadership, The Leadership Code, Leadership for Dummies (of course)--can make you think it has replaced dieting as a way to move merchandise. Listen to politicians' stump speeches, and it will be seconds before you hear them extol their unique leadership qualities.

But leadership, at least in the way that it's understood in the U.S., is not an idea--or even a word--that travels very well. It's remarkably hard to convey in French, while Germans routinely go through linguistic contortions to...